This article will take you through the reasons for a “String match found/not found” root cause on an uptime test:

• In the case of “String match not found” this means that the string you are looking for in the uptime test settings was not found in the page source of the target URL. The setting on the test defines that we should mark a downtime and send an alert if the specified string is not found on the page.
• In the case of “String match found” this means that the string you are looking for in the uptime test settings was found in the page source of the target URL. The setting on the test has been configured to define that we should mark a downtime and send an alert if the specified string is found on the page.
• You may be seeing this error due to trying to match a string that is generated past the point of page load, by JavaScript or other dynamic scripts – string match cannot check or alert based on this content.